U.S. Pat. No. 2,254,961 discloses such lighting units. These lighting units, in a target region normal to the direction of radiation from the lighting unit and illuminated by it, illuminate approximately circular zones. If a rectangular target region is to be illuminated, a large reflector is required.
The present invention, then, is addressed to the problem of developing a compact lighting unit making possible a uniformly high light yield in a prescribed target region.